On Tuesday night, the Pittsburgh Pirates joined the Angels, Cardinals, Dodgers, Nationals and Orioles in clinching a postseason berth. Four other teams (the Athletics, Giants, Royals and Tigers) are in playoff position. The four other teams still alive in the postseason race — the Brewers, Indians, Mariners and Yankees — entered play on Wednesday three or more games out of the playoff picture with just five games remaining. That all adds up to what looks like a dud of a final week for pennant races. However, there are two races that are going down to the wire: the battle for the two Central division championships.

In the National League, both Pittsburgh and St. Louis have clinched playoff spots and will be playing in the postseason. But the Cardinals, who lost Tuesday night to the Cubs, holds a mere 1 1/2-game lead over the Pirates atop the NL Central, and are only ahead by one in the loss column. Over in the American League, a single game is all that separates the division-leading Tigers and second-place Royals.

As recently as 2011, the idea of two teams with playoff berths well in hand jockeying for a division title was of little interest, as both would be delivered directly to the best-of-five Division Series regardless of their order of finish. With the introduction of the second wild-card in 2012, however, winning one's division has taken on far greater importance.

That, of course, was the entire idea behind the introduction of that second wild-card spot: making a division title matter. Forcing the two wild-card teams to play a one-game playoff for the right to advance to the Division Series reduces their season to something close to a coin flip. Even the worst team in the major leagues has a solid chance to win a single game against the best. That's even more pronounced when the two teams involved are of nearly equal quality, as is the case with the two wild-card entrants.

Given that, Pittsburgh and St. Louis have really only clinched one playoff game, while Kansas City and Detroit — the latter of which can clinch a playoff spot with a win and a Mariners loss Wednesday night — likewise have nothing more than that one-game playoff in hand.

Those races are made all the more compelling by the teams involved. In both cases, a postseason fixture is being challenged by a team that has gone decades since its last division title. The Pirates haven't won their division since 1992, when they were still in the NL East, while the Cardinals have won seven NL Central crowns in the last 14 years. In the AL, the Tigers have won the Central each of the last three years, while the Royals — on the verge of breaking the longest postseason drought in the majors — last won their division, then the AL West, in 1985, nine years before the central divisions were even created.

Unfortunately, neither pair of competitors has any head-to-head games remaining. The Royals are finishing the season on the road with a game in Cleveland on Wednesday night, followed by four against the White Sox in Chicago, where they are 5-1 thus far this season. That could be to Kansas City's advantage, however, as it has played far better on the road this season that at home. The Royals also benefit from having restored Danny Duffy to their rotation this past week. Duffy, who threw six scoreless innings against the Indians on Monday, will start the penultimate game of the season against the White Sox, followed by Yordano Ventura, who threw seven scoreless Tuesday night, in the season finale. Ace James Shields, who will start on Thursday night, would then be lined up to start the Wild-Card Game or Game 1 of the Division Series.

The Tigers, meanwhile, finish up with the White Sox on Wednesday night, then welcome the Twins to Comerica Park. That sounds like as easy a path as that of the Royals, but Detroit is just 7-8 against Minnesota this season and just dropped two of three in Target Field last week. The Tigers will send Kyle Lobstein and David Price to the mound in the final two games of the season; Price has given up five or more runs in three of his last six starts, including one of those losses in Minneapolis last week. Detroit would then have Max Scherzer, who will start the opener of that Twins series on Thursday night, lined up to start its first postseason game.

In the NL, the Pirates have two more games in Atlanta followed by three in Cincinnati. Unlike the Royals, Pittsburgh has struggled on the road this season, going just 35-41 away from PNC Park, albeit with exactly as many runs scored as allowed. Nonetheless, the Bucs are so hot right now it doesn't seem to matter where or whom they are playing: Their playoff-clinching win Tuesday night was their 15th victory in their last 18 games. Still, that final stretch will be a significant test for the Pirates. Not only have they been a losing team on the road on the season as a whole, but they are also 6-10 against the Reds, including just 2-4 in Cincinnati.

Gerrit Cole — whose late-August return from the disabled list has been an important part of the team's late surge — is lined up to start Pittsburgh's final game of the season. Edinson Volquez, who is 4-0 with a 1.53 ERA in his last nine starts, is slated to start the Wild-Card Game, if necessary.

The big twist in the NL race is that the Cardinals have just four games remaining: one in Wrigley Field and three in Arizona against the Diamondbacks, whom the Redbirds swept at Busch Stadium in their only other meeting this year back in May. If the Pirates lose behind Volquez on Thursday night while St. Louis is idle, the Cardinals' advantage will become two games.

Meanwhile, the off-day gives St. Louis the option of using Tuesday night's starter, Shelby Miller, in relief over the weekend if needed. It also lines up Adam Wainwright for the final game of the season. That puts the Cardinals in the enviable position of having their best pitcher, and one of the best pitchers in baseball, on the mound for the final day if the division race requires it. Furthermore, with the Division Series not starting until Friday, Oct. 3, Wainwright would be on full rest again for Game 1 of the NLDS.

However, if the Pirates manage to claim the division on the final day of the season, St. Louis will have burned Wainwright on Sunday and will have to choose from among Michael Wacha (who hasn't thrown 80 or more pitches in a game since June), John Lackey (who gave up eight runs in eight innings in his first two starts this month), and Miller to start Wednesday's Wild-Card Game.

Further complicating things: If either division ends in a tie, there will be a one-game playoff between the two rivals on Monday, with the Pirates, Royals and Tigers stuck with their Wednesday night starters (Jeff Locke, Jason Vargas and Justin Verlander, respectively) and the Cardinals forced to choose from between Miller and Lackey. In the AL, that would mean the wild-card team coming out of the Central would play crucial games three days in a row against three different opponents, with game 162 on Sunday, the division tie-breaker on Monday and the Wild-Card Game on Tuesday. So, as much as the postseason field may look set with five games left to go, Team Entropy still has a fighting chance in the central divisions.